Combination pin for attaching trigger assembly and safing small arm

ABSTRACT

A dual-purpose safety and retaining pin which performs the functions of  sng the trigger assembly for a small arm and of securing the trigger assembly to the weapon is provided. The pin comprises a handle attached to a retainer and pin assembly which can be rotated to select safe or arm positions. The retainer and pin assembly is oriented in a specific rotational position with respect to the handle so that safing by rotating the pin can be accomplished. The pin has a cam configuration whereby rotation of the pin causes the cam to move a trigger connector link into contact with a hammer sear. This action enables the weapon. When the pin is rotated to the safe position or when the pin is removed from the trigger housing, the weapon is disabled. The pin is held in position by a plunger-ball locking arrangement. The single spring used to extend the plunger also acts as a detent engaging spring for securing the rotational position of the pin.

ORIGIN OF THE INVENTION

The invention described herein was made in the performance of officialduties by an employee of the Department of the Navy and may bemanufactured, used, licensed by or for the Government for anygovernmental purpose without payment of any royalties thereon.

FIELD OF THE INVENTION

The invention is related to the field of gun safety devices and inparticular to safety pins for small arms.

BACKGROUND OF THE INVENTION

A variety of devices for safing trigger assemblies is known in the art.There are numerous examples of trigger blocking mechanisms and numerousexamples of trigger guard covers which prevent access to the trigger.Additionally, there are a few examples of insertable pins designed todisable the weapon whenever the pin is removed. One such example is U.S.Pat. No. 3,673,725 by James A. Cravener wherein a pin is inserted into asmall arm in order to enable operation. Although Cravener states that adevice such as his is impractical for field use, certain small armsrequire disassembly in the field. An example is the Shoulder-LaunchedMulti-purpose Assault Weapon (SMAW), wherein removal of the triggerassembly is sometimes required to clear certain malfunctions. The SMAWis a rocket launcher/spotting rifle combination configured in anover-and-under design with the rocket launcher tube over the spottingrifle. During removal of the trigger assembly in this weapon, it isessential that both the rocket firing mechanism and spotting rifle beproperly safed. Additionally, it is desirable that the two firingmechanisms remain safe during re-assembly of the weapon.

SUMMARY OF THE INVENTION

Accordingly, it is an object of the present invention to provide acombination safety and retaining pin which provides safe and armpositions when installed.

It is another object of the invention to provide a combination safetyand retaining pin which attaches a trigger housing to a small arm.

It is yet another object of the invention to provide a combinationsafety and retaining pin which safeties the trigger assembly when thepin is removed.

It is still another object of the invention to provide a safety andretaining pin which must be removed prior to removal of the triggerassembly.

Accordingly, the invention is a dual-purpose safety and retaining pinwhich performs the functions of safing the trigger assembly for a smallarm and of securing the trigger assembly to the weapon. The pincomprises a handle attached to a retainer and pin assembly which can berotated to select safe or arm positions. The retainer and pin assemblyis oriented in a specific rotational position with respect to the handleso that safing by rotating the pin can be accomplished. The pin has acam configuration whereby rotation of the pin causes the cam to move atrigger connector link into contact with a hammer sear. This actionenables the weapon. When the pin is rotated to the safe position or whenthe pin is removed from the trigger housing, the weapon is disabled. Thepin is held in position by a plunger-ball locking arrangement. Thesingle spring used to extend the plunger also acts as a detent engagingspring for securing the rotational position of the pin.

BRIEF DESCRIPTION OF THE DRAWINGS

The foregoing objects and other advantages of the present invention willbe more fully understood from the following detailed description andreference to the appended drawings wherein:

FIG. 1 is a side view of the combination pin;

FIG. 2 is an end view of the combination pin;

FIG. 3 is a sectional side view of the combination pin;

FIG. 4 is a perspective view of a trigger housing plate; and

FIG. 5 is a cross-sectional top view showing the combination pininstalled in a trigger assembly.

FIG. 6 is a perspective view of a trigger assembly.

DETAILED DESCRIPTION OF THE INVENTION

Referring now to FIG. 1, the combination pin, designated generally bythe reference numeral 10, for attaching and safing a small arm triggerassembly is shown with its external features. The combination pin 10comprises a handle 11 attached to a retainer pin and cam assembly, theretainer pin 13 having a ball-locking mechanism 14. The cam 15 providesan eccentric movement during rotation in order to enable the triggerassembly. At the end of the cam 15 nearest handle 11, adetent-engagement mechanism 17 is affixed.

The shape of the combination pin 10 components may be further understoodby reference to FIG. 2. The handle 11 is rotationally fixed in relationto cam 15 so that the extended cam covers a one-half circle on the lowerright side of the handle 11. With the handle 11 in this position, thesafety detent engagement mechanism 17 is at the top location, 45° awayfrom the center line of handle 11 and located on the noncam side of theretainer pin 13.

Referring now to FIG. 3, a sectional view of the combination pin 10shows the internal mechanism with the assembly. Handle 11 is attached tothe retainer pin and cam assembly 13 and is held in place by spring pin32. The retaining pin and cam assembly (shown with narrowcross-hatching) extends from inside handle 11 to the insertion end ofthe device. The retainer pin and cam assembly is a single piece housinghaving a smaller center bore on the insertion end and a larger centerbore on the handle end. Two slots 33 are cut through the assembly toallow movement of the detent-engagement mechanism. A dual-action spring35 presses the detent-engagement mechanism toward the insertion end ofthe combination pin. The dual-action spring 35 also presses againstwasher 37 which is affixed to the ball locking rod 39. This action urgesthe ball-locking rod 39 toward the handle end of the combination. Withthe ball locking rod in the position shown (outward toward the handle),the locking balls 41 cannot retract and the combination pin 10 is heldin place to secure a trigger assembly to a weapon. When ball-locking rod39 is pressed inward from the handle 11, the locking balls 41 arealigned with the groove 43 in the locking rod 39 thereby releasing thepin and the entire combination pin can then be removed from the triggerassembly.

FIG. 4 shows a trigger housing plate 45 which mates with the combinationpin to provide detents 47 for the detent-engagement mechanism. Aperture49 is shaped to match the cam shape of the combination pin therebyallowing insertion of the combination pin only in the safe position.After insertion, the combination pin may be rotated to arm the weapon.

Referring now to FIG. 5, the combination pin 10 is shown inserted in thetrigger assembly 51 of a typical weapon 52. This installation representsa trigger assembly attached to a Shoulder-Launched Multi-purpose AssaultWeapon (SMAW). The depiction is a top view looking downward. The triggerassembly is inserted into the weapon from the bottom and the combinationpin is then inserted from the side as shown. As the cam action of thepin is required to enable the weapon, the weapon is safe whenever thepin is removed. Additionally, due to the shape of the aperture, thecombination must be inserted in the safe position and fully seatedbefore it can be rotated to the arm position. This feature means thatthe safety of emergency field disassembly of the weapon is greatlyenhanced.

FIG. 6 depicts a typical trigger assembly 51 which may be secured to asmall arm using the combination pin 10 of the present invention.Combination pin 10 is inserted through aperture 65 to secure the triggerassembly 51 to a small arm. In this embodiment, the action of cam 15acts on a sear connector link 61 (shown in phantom in FIG. 6) raising itwhen rotated to a ruing position so as to engage a sear 62. When trigger63 is pulled, the sear releases the hammer. The depiction in FIG. 6 isintended to reflect safing mechanisms conventionally known in the art.However, the combination pin may be used in numerous differentassemblies and safety mechanisms wherever a cam action can safe and arma weapon.

The advantages and novel features of the invention are numerous. Thecombination pin provides a dual function, both safing the triggerassembly and securing it to the weapon. Additionally, the singleoperating spring performs a dual function, both engaging the positiondetent and operating the ball lock mechanism. Further, removal of thepin automatically safes the trigger assembly, thereby preventinginadvertent firing during assembly or disassembly of the weapon. Thedual functions serve to reduce the number and cost of parts, simplifythe design, and improve reliability.

Although the invention has been described relative to a specificembodiment thereof, there are numerous variations and modifications thatwill be readily apparent to those skilled in the art in the light of theabove teachings. It is therefore to be understood that, within the scopeof the appended claims, the invention may be practiced other than asspecifically described.

What is claimed as new and desired to be secured by Letters Patent ofthe United States is:
 1. A combination pin for a small arm comprising:ahandle; a single means, attached to said handle, for attaching a triggerassembly to said small arm and for safing said small arm; and a lockingrod slidably located within said single means for securing and releasingsaid pin from said small arm.
 2. A combination pin for a small arm as inclaim 1 wherein said single means comprises a retainer pin and camassembly.
 3. A combination pin for a small arm as in claim 2 whereinsaid retainer pin and cam assembly further comprises a single piecehousing having an insertion end and a handle end and having a smallercenter bore at the insertion end and a larger center bore at the handleend, the two center bores being connected and thereby forming a singlecenter bore with differing internal diameters at either end, and havingtransverse slots through the pin.
 4. A combination pin for a small armas in claim 3 wherein said retainer pin and cam assembly furthercomprise a detent engagement mechanism slidably attacked to said lockingrod and located within said slots in the retainer pin and cam assembly.5. A combination pin for a small arm as in claim 4 wherein said retainerpin and cam assembly further comprises a dual-action spring urging saiddetent engagement mechanism toward the insertion end of the combinationpin and urging said locking rod toward the handle end of the combinationpin.
 6. A combination pin for attaching and safing a small arm triggerassembly comprising:a retainer pin and cam assembly having an insertionend and a handle end and having a smaller center bore on the insertionend and a larger center bore on the handle end; a plurality of lockingballs located in apertures on said retainer pin and cam assembly; alocking rod having an insertion end and a handle end inserted throughthe center bores of said retainer pin and cam assembly; a washerattached to said locking rod near the handle end of said rod; a detentengagement mechanism slidably engaging said locking rod; a dual-actionspring installed over said locking rod and further located within thelarger center bore section of said retainer pin and cam assembly; ahandle affixed to said retainer pin and cam assembly; and a spring pinlocated in said handle and securing said handle to said retainer pin andcam assembly.